tree fd718ac8012aa60ad855556bc0caa903fe69ac4c
parent cdb346977829885cbd8b1200ca21049b1df242ad
author Divy Le Ray <divy@chelsio.com> 1205392410 -0700
committer Jeff Garzik <jeff@garzik.org> 1205755621 -0400

cxgb3: Fix transmit queue stop mechanism

The last change in the Tx queue stop mechanism opens a window
where the Tx queue might be stopped after pending credits
returned.

Tx credits are returned via a control message generated by the HW.
It returns tx credits on demand, triggered by a completion bit
set in selective transmit packet headers.

The current code can lead to the Tx queue stopped
with all pending credits returned, and the current frame
not triggering a credit return. The Tx queue will then never be
awaken.

The driver could alternatively request a completion for packets
that stop the queue. It's however safer at this point to go back
to the pre-existing behaviour.

Signed-off-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>